Project Summary The overall objective is to develop and test a novel rehabilitative training program for central auditory dysfunction after traumatic brain injury. Solutions designed to enhance auditory processing when hearing thresholds are within normal limits are very limited and none are as recognized or as widely available as are hearing aids and cochlear implants. While there exist some contemporary approaches devised to improve hearing in a variety of populations, these are largely based upon emulating hearing scenarios in the environment. While such programs show some efficacy, three key limitations undermine the overall effectiveness and deployment of these approaches. 1) A lack of alignment of treatments with up-to-date knowledge of how sounds are processed by the brain 2). A lack of alignment of treatments with up-to-date knowledge of perceptual learning research, and 3) Difficulty in getting patients to comply with training procedures that are often frustrating and boring. Here we aim to overcome these limitations by integrating contemporary knowledge of auditory neuroscience, perceptual learning, and modern game design to develop and test novel auditory training therapies. Our primary premise is that 1) Studies of auditory neuroscience and psychoacoustics have advanced our understanding of the function of auditory processes beyond the cochlea. 2) Studies of perceptual learning have advanced our understanding of plasticity in the neural systems underlying hearing, and have refined behavioral procedures that engage these systems. 3) Commercial video games have become ubiquitous, sophisticated, and shaped by competitive market pressures to become both perceptually engaging (rich graphics, sounds, and animations) and cognitively challenging. Combining these elements can lead to behavioral cognitive therapies that are effective and encourage compliance by being compelling, stimulating, and fun. We will test an adaptive training program that involves practice with a ?basis set? of spectral temporal modulated sounds that are modeled after auditory neuron receptive field properties7 combined with interaural localization cues to also train sound source segregation. Efficacy will then be tested in normal hearing participants and in patients with mild traumatic brain injury and auditory processing difficulties (APDs) and compared against active tone training controls. Outcome measures are tests of real world audition including; speech in noise, multiple talker environments and auditory attention and working memory. Potential for knowledge gain and translational impact is substantial. This project will result in techniques and data relevant to rehabilitation of APDs. The data and training will be made available to the clinical and research community. Evidence of efficacy will be followed upon with a R01 proposal to examine how different components of training contribute to observed effects and to examine neural underpinnings. The positive impact whether or not the training program is effective will be new knowledge about what types of training programs are effective, and which are not, and can contribute to development of effective therapies for APDs.